\"\"\"\"

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The measurement of segment RT is the distance between point R and T.

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Observe the figure; the point S divides the line segment into two line segments RS

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and ST.

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Length of \"\"= Length of \"\" + Length of \"\"

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\"\"            (Substitute \"\" and \"\")

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\"\"    (Subtract 1.2 from each side.)

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\"\"    (Commutative property of Addition: \"\")

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\"\"                 (Additive inverse property: \"\")

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\"\"                       (Additive identity property: \"\")

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\"\"                                (Subtract: \"\")

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\"\"

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\"\"

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The length of the segment \"\"

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